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Formerly alpha/memchr.c.~2~
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@ -44,22 +44,29 @@ memchr (const void *s, int c, size_t n)
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for (;;)
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{
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int mask;
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asm ("cmpbge %1, %2, %0"
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: "=r" (mask) : "r" (charmask), "r" (*longword_ptr++));
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if (mask)
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const unsigned long int longword = *longword_ptr++;
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int ge, le;
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/* Set bits in GE if bytes in CHARMASK are >= bytes in LONGWORD. */
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asm ("cmpbge %1, %2, %0" : "=r" (ge) : "r" (charmask), "r" (longword));
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/* Set bits in LE if bytes in CHARMASK are <= bytes in LONGWORD. */
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asm ("cmpbge %2, %1, %0" : "=r" (le) : "r" (charmask), "r" (longword));
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/* Bytes that are both <= and >= are == to C. */
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if (ge & le)
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{
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/* Which of the bytes was the C? */
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const char *cp = (const char *) (longword_ptr - 1);
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if (cp[0] == c)
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return cp - str;
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return cp;
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if (cp[1] == c)
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return cp - str + 1;
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return &cp[1];
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if (cp[2] == c)
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return cp - str + 2;
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return cp - str + 3;
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return &cp[2];
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return &cp[3];
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}
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}
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}
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